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This is a list of succinct tasks that are expected to take most people familiar with the prerequisites less than two hours to complete. It's a great starting point for anyone interested in contributing to BRL-CAD.

The tasks are all roughly the same complexity with no prior BRL-CAD experience expected. A description is provided along with a list of references and files you'll probably need to edit. Can we make it any easier?

We break down all tasks into one of five categories. Don't be worried if the tasks all sound confusing to you. Just pick one and start reading the references we've provided. Join IRC or our mailing list and ask questions.

BRL-CAD provides functions for its geometric primitives that define a bounding box - a box that completely encloses the volume described by the primitive. Ideally, these boxes are as small as possible while still enclosing the primitive. Currently the routine for BoTs is incorrect. You can use stl-g, obj-g, or any of our other *-g converters to import BoT geometry for testing.

This task involves studying the current code for the function rt_bot_bbox() and determining what is causing the current inaccuracies (the mged 'bb' command is a good way to visualize primitive bounding boxes). Make changes to produce a more optimal bounding box. Reimplement it from scratch if you like. The raytracing prep code in rt_bot_prep does prepare a better bounding box, so that is one place to check.

BRL-CAD has an interactive geometry editor called MGED. It's often the starting point for beginners and allows creation and manipulation of models using commands. When mged is run, it creates 2 windows: a text-console command window and an interactive graphics window. When the user closes one of those windows, there is a bug. Closing the graphics window closes the command window.

This task involves fixing this behavior so that ONLY closing both windows terminates the process properly and that closing either window does not take the other along with it.

BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones. Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoid. Wikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are a little more tricky to compute.

This task involves writing a new callback function that takes an rt_db_internal object and calculates its centroid (as a point_t 3D point). There are numerous examples in our code where we compute centroids for other primtiives. The primitives that do not already have a centroid callback are itemized in following.

BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones each described by a collection of callback functions, for example rt_sph_bbox() returns the bounding box dimensions for a sphere. Wikipedia, Wolfram Mathworld, and various other math sites (and research papers) around the web include the equations for most of our basic primitives while others are a little more tricky to compute.

This task involves writing the callback function rt_xxx_curve() that computes the curvature at a given point on the surface of a primitive such as;

superell

cline

extrude

grip

metaball

hrt.

There are numerous examples in our code where we compute the curvature for other primtives like the ellipsoid, sphere, elliptical parabola, etc.

include/raytrace.h: See the data structure that holds the curvature of a surface at a point (from Line 296) as well as the prototype for ft_curve() callback function defined in the rt_functab structure ( Line 2078).

BRL-CAD provides more than two dozen types of geometry "primitives" such as ellipsoids, boxes, and cones. Every primitive is described by a collection of callback functions, for example rt_ell_bbox() returns the bounding box dimensions for an ellipsoid. One of those functions describes a UV mapping of the object's surface, which is used for things like texture and bump mapping. An example of this is rt_ell_uv() in the src/librt/primitives/ell/ell.c source file for an ellipsoid. Several of our more complex primitive types (such as BoT, NMG, and BREP/NURBS) do not presently implement a UV-mapping function leading to unexpected runtime behavior.

This task involves implementing a UV-mapping callback for any of the primitives that do not already have a functional UV-callback defined. Note that this is an advanced task that might take you more than a couple hours if you don't have solid coding skills, but it's ultimately just a few lines of code. See other primitives that already implement a UV-mapping callback for reference.

The classic C library qsort() does not support a context parameter. A work around is to store the context information in a static variable. However, this solution is not thread save and may result in unpredictable behavior.

There are platform specific sort functions qsort_r() in incompatible versions for BSD and GNU and qsort_s() for MSVC. Your task is to implement a bu_sort() function for BRL-CAD which is platform independent.

BRL-CAD has been working on a new incarnation of the website and has developed a new wiki theme and wordpress theme. Wiki theme uses a font called 'open-sans' from google fonts directory. It's linked via CSS but it does not get loaded (we still see default serif all over the place). So your task will be to debug the CSS code and get Open Sans loaded.

BRL-CAD has been working on a new incarnation of the website and has developed a new wiki theme and wordpress theme. Wiki theme is responsive but has a small styling problem. On smaller screens icons near the search bar gets misplaced and unaligned. Your task would be to fix that. Task would include diving into sass file that corresponds to styling of this part of theme (given below) and adjusting spacing between icons to keep them aligned even at smaller screens.

This task involves writing basic documentation for JUST ONE of those commands in the Docbook XML format. The command documentation should provide a one-sentence description, a detailed paragraph description (200+ words), explanation of all available command-line options, and one or more examples on how to use the command.

Although BRL-CAD has extensive documentation, still it needs a short and simple document which is particularly built for dummies.

This task involves writing a article named BRL-CAD for dummies. This article should start with the installation process, if there is any existing installation guide for dummies, provide a link to it. The main motive of this article to empower dummy to make his/her first model using BRL-CAD. One thing to be kept in mind while writing this article is that this article is mainly concentrated for dummies. So use simple language to an extent and if you need to mention some technical term, first explain that term.

The output of this task can be a pdf, html, doc, odt or any other document file that contains this article. Go through the link provided. Use screenshots and images to make it look attractive so that the reader is not bored.

People interested in improving BRL-CAD sometimes find themselves lost in a sea of information. In all, BRL-CAD has more than a million words of documentation across hundreds of manual pages, dozens of tutorials and examples, hundreds of wiki pages, dozens of technical papers, and other resources. There are literally thousands of features and this can sometimes pose problems.

In 2013, a team of contributors got to California and worked on an entire book titled "Contributors Guide To BRL-CAD" in just a few days. This great resource needs to be translated to other languages to attract developers from other lingual backgrounds (who don't read English ) to contribute to BRL-CAD.

This task involves translating the chapters/sections of the "Contributors Guide To BRL-CAD" into a language of your choice such as Mandarin, French, Chinese, Spanish, German, Hindi, Arabic, Russian, etc. Chapters/Sections include

Feature Overview

Working with our Code

What code to work on

How to contribute

.... (Just to name a few )

The output of this task can be a pdf, html, doc, odt or any other document file that contains the translated article.Images in the original document (see link in Reference below) should not be changed ! only text should be.

BRL-CAD uses Doxygen for most API documentation but the comment blocks are not optimally set up for Doxygen output.

This task involves cleaning up the Doxygen comments in the library so that useful reports and API documentation automatically generated (correctly, completely, and cleanly). Verify/fix any Doxygen syntax. Verify/fix groups so that functions are organized neatly and all contained within a group. Provide patches that give clean (PDF) output from Doxygen.

BRL-CAD provides a couple dozen distinct primitives. Each primitive is defined by a set of parameters. Several of the more complex primitives have a wiki page describing them in more detail with an example on how to create them.

This task involves writing up a page on the VOL primitive. Figure out how to use it (see the "in" command), create an example input data set, and write up a wiki page on exactly what steps are needed similar to our other wiki pages:

Show how to create a VOL with at least two layers/slices. Include images like the other examples. Put the write-up at http://brlcad.org/wiki/VOL

Write a wiki tutorial on how to create a polygonal mesh (NMG) manually[edit]

BRL-CAD provides a couple dozen distinct primitives. Each primitive is defined by a set of parameters. Several of the more complex primitives have a wiki page describing them in more detail with an example on how to create them.

This task involves writing up a page on the NMG polygonal mesh primitive. Figure out how to use it (not a simple task, will require some trial and error), create an example input, and write up a wiki page on exactly what steps are needed similar to our other wiki pages:

The majority of BRL-CAD's documentation is defined as DocBook files, from which other formats (HTML, PDF, man page, etc.) can be generated. PDF files present a particular challenge, and have some very specific requirements to achieve "good" formatting.

BRL-CAD's DocBook files need to uniformly use a style of image inclusion that is aware of what "role" the image is supposed to serve. A "basic" image inclusion example looks like this:

The "role" flag to imageobject provides the opportunity to specify different image formatting options when the output is HTML (role="html") or PDF (role="fo").

The captions should be preserved as above on mediaobjects that have them, but mediaobjects without a caption should also be converted and there is no need to add a caption in such cases.

Any patch that makes changes to the DocBook sources should result in a successful "make doc" build test. This won't generate PDF documents, but it will validate the XML files and produce HTML - remember that introducing breakage means the patch won't be accepted.

Remember, the tasks are simply to do the above conversion for all images in the file or files, not to introduce PDF specific formatting. Formatting fixes will be needed, but they are very much "case by case" and will take both additional time and a working Apache FOP installation, as well as knowledge of how to enable PDF generation. If all image inclusions have been converted successfully and a student is interested in actually fixing the formatting, please discuss it with us on IRC or the mailing list.

Online Geometry Viewer is a web based application with which you can see 3D .g models in browser without the use of any plugins. Your task will be to deploy OGV locally and find 5 bugs or errors in it.

Online Geometry Viewer is a web based application with which you can see 3D .g models in browser without the use of any plugins. Your task will be to deploy OGV locally, look into code and see if any coding guidelines are violated.

BRL-CAD implements support for rendering of NURBS representation geometry. If you import a solid 3DM or STEP format model into BRL-CAD, it will import as BREP/NURBS geometry. Opening that geometry in BRL-CAD's MGED editor will tell you what objects are available and our 'rt' tool will raytrace it. When geometry is ray traced, it first goes through a "prep" phase and then it starts shooting rays. Our prep phase is entirely unoptimized so we'd like to know where all the time is presently being spent during prep..

This task involves importing some NURBS geometry into BRL-CAD and ray tracing that geometry with a profiler watching our prep performance. Any profiler will do, including gprof, but a performance monitor like oprofile or the Mac "Instruments" application (or Shark) are preferred.

Learning how to use a profiler is beyond the scope of this task, so it make take you considerably longer to provide us with useful information if you've never run a profiler before.

To capture prep performance, you will need to import some fairly complex geometry. You should be able to search google with "filetype:3dm" or "filetype:step" or find something on grabcad.com to import

Running "tops" within mged will tell you what geometry is available for rendering.

Running "rt -o file.png -s32" on the system command line (not inside mged) should minimize the ray overhead or you can specifically isolate the prep phase we care about. Prep is the time between when rt is run where it opens a window until the first pixels are fired and pixels start filling in.

BRL-CAD uses a fastf_t typedef for most all math operations that is usually a "double" floating point type. We would like to provide the option for resorting to exact arithmetic if possible by merely redefining fastf_t to a C++ type sufficiently overloaded to behave the same. You should be proficient with C++ operator overloading to take this work on. This task is a continuation of a prior GCI task (read it in full!):

This task involves testing compilation with a C++ class with overloaded operators such that vmath macro calls still work as well as a sampling of LIBBN API function calls without major changes to the original code. A perfect example case study would be creating the class then testing whether bn_dist_pt3_pt3() and bn_mat_determinant() compute correctly for values that cannot be exactly represented with floating point arithmetic.

Building on the previous GCI task work, take it to the next step. Try setting a vector to 1/3, 1/3, 1/3 and 0.1, 0.1, 0.1 and get proper values to print. Change the V3ARGS() macro if needed. If that all works, try to get bn_dist_pt3_pt3() to work. Report and discuss your progress.

This task involves designing a T-Shirt for BRL-CAD. Use your designing skills to design a T-Shirt for BRL-CAD. You can use the current BRL-CAD logo, or you may tweak it. Be creative while designing this T-Shirt. It would be good if the design has some special meaning.

This task involves designing a coffee mug for BRL-CAD. Make it look good, so that one can use it while working on BRL-CAD. Look over some great coffee mug designs before starting to work on this. It would be great if the design on coffee mug has some special meaning.

This task involves designing a BRL-CAD sticker. The design should be simple and sleek. The concept of sticker should be clear and also it should be creatively presented. Get inspired from some sticker designs but choose your own imagination while designing the sticker. There is no bound for shape of sticker, it can be rectangular, circular or even irregular. The only thing that matters is that it should look good.

This task involves designing a BRL-CAD phone/tablet cover.
While submitting your design, provide the sample phone cover, tablet cover with the design and rendered png or jpg image of the sticker design. Try to have a special meaning of design, and the concept should be creatively illustrated.

This task involves designing a set of wallpapers for BRL-CAD. The central idea of each wallpaper should represent any feature of BRL-CAD. Try to design a minimum of 5 wallpapers but if you have more than 5 designs than you are welcomed.

You might have heard and praised those google doodles we occasionally see on google.com on special days. This task is all about tweaking BRL-CAD logo to wish New Year. You may have a look at google doodles but don't entirely copy their style. I am sure your creative mind will get something much better.
Make sure this tweak should be tweaked version of current logo and not entirely new logo.

Tip: Search for some global events occurring in 2015 and design accordingly. Also keep the letters 2,0,1,5 in mind while designing. ;)

Also output of this task shall be the png file of your work and the raw file but don't upload the raw file(.psd, .xcf or some other) for review of this task. We will ask for it later, when the design is finalized.

You might have heard and praised those google doodles we occasionally see on google.com on special days. This task is all about tweaking BRL-CAD logo to wish Christmas. You may have a look at google doodles but don't entirely copy their style. I am sure your creative mind will get something much better.
Make sure the output of this task should be tweaked version of current logo and not entirely new logo.

Also output of this task shall be the png file of your work and the raw file but don't upload the raw file(.psd, .xcf or some other) for review of this task. We will ask for it later, when the design is finalized.

By default, all of BRL-CAD compiles using double-precision floating point arithmetic. We provide a simple typedef, however, that converts almost the entire system over to single-precision floating point. This compilation mode was recently cleaned up and tested, but a bug was found. The problem is reproduced very simply by compiling in single precision mode and running our "rt" ray tracer tool.

To compile in single precision, edit the include/bn.h header file and change the fastf_t typedef from double to float. To reproduce the bug, compile BRL-CAD and write this out to a text file named star.view:

BRL-CAD geometry editor application (mged) has several hundred commands including two very simple commands for opening and closing a geometry database file. While the user rarely ever needs to close the file, as all changes are always immediately saved, it can be of use to scripting applications. However, at some point in the recent past, the closedb command was horked. It's undoubtedly something very simple but we haven't bothered to look due to other priorities. You can fix it. If you run these simple steps within graphical mged, you should see how commands stop working after calling closedb:

Provide a patch that fixes the bug or tell us which SVN revision introduced the bug. Make sure you can reproduce the bug before claiming this task, which presumes you know how to download/install BRL-CAD from a source distribution.

There are more than 300 library functions in our core LIBBU library. As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.

This task involves implementing new unit tests for any of LIBBU's source files that do not already have a unit test defined. The test should run all of the public functions and be hooked into our build system. We have lots of existing unit tests to follow as examples.

There are more than 300 library functions in our core LIBBN library. As a core library used by nearly every one of BRL-CAD's tools, testing those functions for correct behavior is important.

This task involves implementing new unit tests for any of LIBBN's source files that do not already have a unit test defined. The test should run all of the public functions and be hooked into our build system. We have lots of existing unit tests to follow as examples.

References:

include/bn.h

include/plot3.h

include/vmath.h

src/libbn/*.c

src/libbn/tests/*.c <-- check this directory for examples

src/libbu/tests/*.c <-- Note: Also check this too for more examples.

Code:

src/libbn/tests/[TEST].c

src/libbn/tests/CMakeLists.txt

Note
A valid task will constitute writing a basic test for each function in the following libbn/ files.

Archer is our new modeling interface and a soon to merge with our long-standing MGED geometry editor. It undoubtedly has bugs. It's your job to find one, but do so in a manner that is so obvious that one of the other devs will be able to instantly reproduce the bug given your specific instructions. Find a way to make archer crash, become unresponsive, or otherwise behave incorrectly. You will have to explore the tool with minimal documentation.

This task involves filing a bug report with verifiable and reproducible steps that clearly demonstrate the bug. It can't be a bug already reported or otherwise documented nor can it be merely behavior you don't like.

BRL-CAD presently has approximately 75 open bug reports of which 50 are unassigned. Read the comments and status to see if the bug has been confirmed/reproduced.

This task involves going through those reports and REPRODUCE at least 10 of the ones that have not been confirmed. When you can reproduce the issue being reported, you'll comment on the thread to state as much and attach any data you used to reproduce the crash.

Everyone loves to see screenshots and animations of software in action. We use both in our marketing and outreach. See some of the examples below that we already have.

Create an awesome screenshot and/or animation of our 'isst' tool in action. It's an interactive geometry viewer interface. It should be graphically interesting and give some sense of capability. You should import a visually complex and interesting model with LOTS of polygons and detail.

Note that we have several screenshot tasks. Note you may have to go through some or our basic MGED tutorials (see docs section on our website) just to be able to display geometry. Finally, give others a chance if you already completed one of the other screenshot tasks. ;)

BRL-CAD is a suite of more than 400 processing tools, image tools, geometry converters, and more. There is an existing spreadsheet that characterizes all of the available commands in terms of inputs, outputs, and options, but there is insufficient characterization of BRL-CAD's commands as to how they logically group and work together.

This task involves building up a spreadsheet that lists all of our commands, describing a finite set of command categories, and characterizing all commands into those categories while filling in the spreadsheet with details for each command.

References:

A spreadsheet template will be provided.

Design a Cover Photo for Facebook page (and other social networks)[edit]

BRL-CAD got it's logo changed, and it's website is undergoing a change. So this re-branding of BRL-CAD also requires a good, well designed and attractive cover photo for the BRL-CAD's Facebook page or other Social Media Appearances. It should feature a good tagline telling some killer feature of BRL-CAD, BRL-CAD's new logo and/or some illustration/image regarding the feature highlighted in tagline.

It should be consistent with the color scheme of our new website design.

BRL-CAD is one of the oldest open source communities. This community has a good following, so we want to give a chance to everyone so that they can show their support to the community by adding a banner ad in their website. You have to create a banner ad that can be embedded in the website by copy pasting some simple lines of code (basically an iframe).

Such a banner ad can also be used in various sections of our own website.

The task requires you to create a CSS3 based animated horizontal and vertical banner add, highlighting some feature of BRL-CAD or making some call to action. This call to action can be joining mailing list, or signing up for community, or link to latest post etc.

BRL-CAD has a lot of great features that can be highlighted. A motion typography video highlighting these features would be a wonderful addition to the front page of website.

This task requires you to create a motion typography video that will convince user to give BRL-CAD a try, it could be titled something like "x reasons to choose BRL-CAD" or anything similar (give your creative minds a flight). The video should not be more than 2 minutes.

Getting started with BRL-CAD is sometimes not so smooth. A screen-cast giving a tour of BRL-CAD's GUI and the steps involved in creating the first model will make it easy for users to get started.

For this task you need to install BRL-CAD on your computer. Create a very basic model in it and record your screen as you create the model. It should also give a tour of BRL-CAD's workspace. You can choose model of your choice. Keep something very basic and easy for the first time users.

We love our developers and want to have a special place in it's website to thank and motivate hard working folks behind BRL-CAD. Your task would be to use an image manipulation software such as GIMP or Photoshop and design a hall of fame page for developers. It should have avatars and names of all the developers. For inspiration you can take a look at http://underscores.me/. You are free to experiment and design anyway you want, just make sure that the color scheme and font-scheme is consistent with the new BRL-CAD web design.

For non-code, just send us your file(s). For code changes, you will be expected to provide a patch file. Make sure you read your patch file before submitting it. Make sure your patch file will apply cleanly to an unmodified checkout of BRL-CAD:

"Prohibition...goes beyond the bounds of reason in that it attempts to
control a man's appetite by legislation and makes a crime out of things
that are not crimes. A prohibition law strikes a blow at the very
principles upon which our government was founded." - Abraham Lincoln, 1840

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